As an example of a copolymer having repeating units of acrylate derivatives in which a polyalkylene oxide chain is present at the site of ester moiety, or an example of a polymer solid electrolyte using these, a polymer solid electrolyte including a cross-linked polymer matrix component (A) and electrolytic salt (B), characterized in that, in the polymer solid electrolyte produced by a polymerization reaction of the matrix component (A), the matrix component (A) contains at least a urethane (meth)acrylate compound (A1) and a polymerizing monomer (A2) represented by the general Formula (1) below is known (refer to Japanese Laid-Open Patent Application No. 2002-216845).

Also, a multi-branched polymer obtained by copolymerizing a mixture of monomers which includes at least a monomer (A) represented by the Formula (2):
(wherein each of R111 to R113 independently represents a hydrogen atom or an alkyl group having 1-4 carbon atoms, R114 represents a hydrogen atom, an alkyl group having 1-4 carbon atoms or an acyl group having 1-4 carbon atoms; and n represents an integer of 1 to 20), and
a monomer (B) represented by the Formula (3):
(wherein each of R115 to R117 independently represents a hydrogen atom or an alkyl group having 1-4 carbon atoms; each of R118 to R122 independently represents a hydrogen atom, a halogen atom, an alkyl group having 1-4 carbon atoms or a haloalkyl group having 1-4 carbon atoms; and at least one of R8 to R12 is a α-haloalkyl group having 1-4 carbon atoms), and a solid electrolyte produced by using thereof are known (refer to Japanese Laid-Open Patent Application No. 2001-181352.)
Moreover, a block copolymer composition characterized by including: (1) a block copolymer including a segment A having 10-100 mol % of at least one polar monomer selected from the group of the following polar monomers 1, 2 and 3, and a segment B having less than 10 mol % of the polar monomers; and (2) an ester compound, and a solid electrolyte produced by using thereof are known.
Polar monomer 1: a polar monomer which contains at least one polymerizable unsaturated bond and at least one functional group selected from the group consisting of hydroxyl, nitrile, carboxyl, amino, and amide group.
Polar monomer 2: a polar monomer which is represented by theCH2═CR201—COO—(CH2—CHR202—O)t—R203  (4)following general Formula (4):CH2═CR201—COO—(CH2—CHR202—O)t—R203  (4)(wherein each of R201 and R202 represents a hydrogen atom or an alkyl group having 1-5 carbon atoms; R203 represents an alkyl group having 1-5 carbon atoms or a phenyl group; and t represents a repeating number and an integer of 1 to 25).
Polar monomer 3: a polar monomer which is represented by the following general Formula (5):CH2═CR204—COO—(CfH2f—COO)g—R205  (5)(wherein R204 represents an alkyl group having 1-5 carbon atoms; R205 represents an alkyl group having 1-10 carbon atoms or a phenyl group; and each f and g represents a repeating number and integers of 1 to 20) (refer to Japanese Patent Laid-Open Application No. H11-240998.)